Esau

Esau is a character mentioned throughout Mabel.

All Seasons
Esau is Mabel Martin's grandfather, Lily Martin's father, and Sally Martin's husband. None of them took his last name, which is unknown. Little is known about him beyond the fact that he is dead (see Pilgrimage, in which Anna states that he is buried next to Lily).

His name presumably references the biblical Esau, who is the older brother of Jacob. Jacob uses deception to steal Esau's birthright and Esau vows to kill him.